This paper interrogates the complexity of language use at the Grade Three-Four transition, using the South African context as a microcosm of similar educational systems. The paper describes the complex nature of the transition, particularly within a second language (L2) instructional context. It explores the dissonance between and among theory, policy or curriculum, and practice; which aggravates an already complex transition. It draws on Cummins' Basic Interpersonal Communication Skills (BICS) and Cognitive Academic Language Proficiency (CALP) theory, the Linguistic Interdependence Hypothesis (LIH) and the Linguistic Threshold Hypothesis (LTH). Theory is considered in relation to the South African policy and curriculum ideals as espoused in the Language in Education Policy (LiEP) and the Curriculum and Assessment Policy Statement (CAPS) respectively, as well as in relation to the reality of the classroom instructional context. The paper argues for extensive research, which delineates the linguistic needs and thresholds second language learners need for the transition, a consideration of learners' attainment of the requisite linguistic thresholds as a condition for the use of a First Additional Language (FAL) as Language of Learning and Teaching (LoLT), and deliberate teaching for transfer in the Foundation Phase, among other recommendations.